Method of treating coal and product thereof



Patented Feb. 25, 1930 UNITED STATES PATENT OFFICE NATHANIEL R. LANDON, OI MOUNT KISCO, NEW YORK, ASSIGNOR TO DELAWARE, LAOKAWAN NA 6% WESTERN COAL COMPANY, OF NEW YORK, N. Y., A CORPORATION 01 NEW JERSEY METHOD OF TREATING COAL AND PRODUCT THEREOF No Drawing.

This invention relates to the treatment of anthracite coal which has lost its fresh mined characteristic appearance in storage whereby the original appearance is in part or Wholly restored.

Fresh mined coal, that is coal which is mined and shipped for immediate consumption, has a jet black color and bright luster. Owin to the seasonal demand for coal, large quantlties of fresh mined coal are placed in storage whenever possible in order to avert a shortage in the fall and Winter months. Coal so stored does not deteriorate as a fuel but the external appearance is altered. Itassumes a dull greyish black appearance and under prolonged and more severe exposure it may become badly discolored by a surface deposit of metallic oxides and salts.

The consuming public, who are accustomed to recognize anthracite coal by its jet black color and luster, often assume that coal which has been held in storage and has thus lost its characteristic appearance is of poor quality. The original fresh mined appearance cannot be restored by ordinary washing or methods heretofore in use, and consequently serious losses are sustained by the producer because of this storage coal, although analysis indicates that the change is only one of appearance, and that there is no loss in fuel value or consequential change in chemical composition.

It is the object of this invention to provide an effective method of treating coal to restore its original color and luster, specifically anthracite coal which is grey in appearance and which does not carry a heavy deposit of metallic compounds.

. I have found that the moderately weathered coal can be restored in luster by coating it with a material of which thin films or layers have a glossy appearance. In order that there shall be reasonable permanence to the luster, the material used for coating must have relatively low volatility. Substances of widely different properties are suitable for carrying out this invention and they may be applied by varying methods depending on the individual properties of the substance.

For example, many water soluble liquid Application filed February 25, 1929. Serial No. 342,684.

and solid substances are suitable, such as glycerine, starch, dextrine, and gum arabic. A satisfactory method of using glycerine is to dissolve one part of glycerine in ten parts of water, and then apply this solution to the coal by dipping, or spraying. On evaporat1on of the water at normal temperatures, the glycerine being of relatively low volatility Wlll cover the surface of the coal with a thin glossy film imparting to the coal the appearance of being freshly mined. Another example of the method consists'in dissolving 10 to parts of yellow or white dextrine in 100 parts of warm water and treating the coal with this solution, draining, and allowing to dry.

Water insoluble liquid substances such as the common mineral, animal and vegetable OllS coated on the coal in thin layers will effectively restore its glossy'appearance. The oil can be applied to the coal, either undiluted or diluted with a solvent by spraying, dipping or otherwise, or preferably the oil can be emulsified with water and'then be sprayed on the coal, or the coal can be dipped in the emulsion and drained. An emulsion of ten parts of heavy mineral oil with 90 parts of stances, as various mixtures containing the.

substances described or equivalent materials may be prepared and applied to the coal to attain the object of the invention.

Also, while the essence of this invention is restoration of the original appearance of coal which has become altered in storage, this sam treatment 01 the coal can be carried out before it goes to storage, and the efiects of store ebe thereby lessened or prevented.

I c aim:

1. Coal having a glossy coating ofa watersoluble substance deposited thereon, whereby the appearance of the coal is im roved.

2. Goal having a coating of g ycerine deposited thereon, whereby the appearance of the coal is improved.

In testimony whereof I afiix my si ature.

NATHANIEL R. LAN ON. 

